Class: QrForge::Renderer

Inherits:
Object
  • Object
show all
Defined in:
lib/qr_forge/renderer.rb

Overview

Renderer class is responsible for generating the SVG representation of a QR code.

It takes QR data, design options, and renders the QR code with finder patterns, alignment patterns, and modules. It also handles the image if provided.

Constant Summary collapse

DEFAULT_COLORS =

Rendering of how row and column indices relate to the finder pattern:

 col_index (x)
0 1 2 3 4 5 6

row_index (y)

0          # # # # # # #
1          # . . . . . #
2          # . # # # . #
3          # . # X # . #   ← (3,3) is inside the finder
4          # . # # # . #
5          # . . . . . #
6          # # # # # # #

Legend:

"#" = dark module (true)
"." = light module (false)
"X" = example point at (row_index=3, col_index=3)

{
  module: "black",
  outer_eye: "black",
  inner_eye: "black"
}.freeze
DEFAULT_COMPONENTS = 
{
  outer_eye: ::QrForge::Components::EyeOuter::Circle,
  inner_eye: ::QrForge::Components::EyeInner::Circle,
  module: ::QrForge::Components::Module::Circle
}.freeze

Instance Method Summary collapse

Constructor Details

#initialize(qr_data:, config:) ⇒ Renderer 



43
44
45
46
47
48
49
50
51
52
 
# File 'lib/qr_forge/renderer.rb', line 43

def initialize(qr_data:, config:)
  @qr_data = qr_data
  @components = DEFAULT_COMPONENTS.merge(config.fetch(:components, {}))
  @quiet_zone = 4
  @module_count = qr_data.module_count
  @image = config.dig(:design, :image)
  @size = config.dig(:output, :size)
  @colors = DEFAULT_COLORS.merge(config.dig(:design, :colors) || {})
  @layout = QrForge::Layout.new(qr_data:, has_image: image_present?)
end

Instance Method Details

#canvas_size ⇒ Integer

Calculates the size of the canvas for the QR code. The canvas size is the module count plus the quiet zone on both sides.

The quiet zone is a margin around the QR code to ensure readability.



81
82
83
 
# File 'lib/qr_forge/renderer.rb', line 81

def canvas_size
  @canvas_size ||= @module_count + (@quiet_zone * 2)
end

#to_svg ⇒ Object

Generates the SVG representation of the QR code.



56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
 
# File 'lib/qr_forge/renderer.rb', line 56

def to_svg
  Nokogiri::XML::Builder.new(encoding: "UTF-8") do |xml|
    xml.svg(
      width: @size,
      height: @size,
      xmlns: "http://www.w3.org/2000/svg",
      viewBox: "0 0 #{canvas_size} #{canvas_size}",
      shape_rendering: "crispEdges"
    ) do
      draw_background(xml)
      draw_image(xml)
      draw_finder_patterns(xml)
      draw_alignment_patterns(xml)
      draw_modules(xml)
    end
  end.to_xml
end